Isolation of Lytic Bacteriophages from Sewage Samples against MDR-Klebsiella pneumoniae and MDR-Enterobacter aerogenes: A potential tool for medical purposes

Abstract

Background: the aim of this study was the isolation of phages able to lyse some strains of MDR-K. pneumoniae (named vB_Kp1 and vB_Kp2) and E. aerogenes (named vB_Ea1) from swages. Materials and Methods: Different Klebsiella pneumoniae and Enterobacter aerogenesis strains isolated from clinical specimens (January to September 2018) in three Hospitals in Amol, (Mazandaran, Iran). Kirby Bauer’s disc diffusion method was used for determination of resistance profiles of these isolates using different antibiotics. The resistant strains to multi tested antibiotics (MDR) were selected to investigate the effect of isolated phages from wastewater and hospital sewage. Presence of phage investigated by plaque formation and after enriching and concentrating the isolated bacteriophages and staining the samples, a transmitting electron microscope (TEM) was used to observe the morphology of the bacteriophages. Phage identification tests including host range and One-step growth were performed. Results: TEM analysis revealed that tree phages have an icosahedral capsid and long contractile tail. Therefore, they are a member of the Myoviridae family. Phages were able to lyse 14 (56%) of the 25 strains of multidrug-resistant bacteria isolated. The one-step growth curve showed large burst sizes and short latent times. Conclusions: The formation of clear plaques shows the high lyse power of phages, so they have good potential for further analysis for clinical use as a therapeutic agent in the future.

Keywords

• klebsiella pneumoniae
• enterobacter aerogenes
• phage therapy
• multidrug-resistant infection